Geomechanics and Engineering

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3D stability of pile stabilized stepped slopes considering seismic and surcharge loads

  • Long Wang (School of Environment and Civil Engineering, Jiangnan University) ;
  • Meijuan Xu (Mechanical Engineering Department, Zhejiang University City College) ;
  • Wei Hu (State Key Laboratory of Geohazard Prevention and Geoenvironmental Protection, Chengdu University of Technology) ;
  • Zehang Qian (Department of Civil Engineering, Central South University) ;
  • Qiujing Pan (Department of Civil Engineering, Central South University)
  • Received : 2021.07.13
  • Accepted : 2023.02.23
  • Published : 2023.03.25
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Abstract

Stepped earth slopes incorporated with anti-slide piles are widely utilized in landslide disaster preventions. Explicit consideration of the three-dimensional (3D) effect in the slope design warrants producing more realistic solutions. A 3D limit analysis of the stability of pile stabilized stepped slopes is performed in light of the kinematic limit analysis theorem. The influences of seismic excitation and surcharge load are both considered from a kinematic perspective. The upper bound solution to the factor of safety is optimized and compared with published solutions, demonstrating the capability and applicability of the proposed method. Comparative studies are performed with respect to the roles of 3D effect, pile location, pile spacing, seismic and surcharge loads in the safety assessments of stepped slopes. The results demonstrate that the stability of pile reinforced stepped slopes differ with that of single stage slopes dramatically. The optimum pile location lies in the upper portion of the slope around Lx/L = 0.9, but may also lies in the shoulder of the bench. The pile reinforcement reaches 10% universally for a looser pile spacing Dc/dp = 5.0, and approaches 70% when the pile spacing reaches Dc/dp = 2.0.

Keywords

Acknowledgement

This research was financially supported by the National Natural Science Foundation of China (Grant Nos. 52208345, 52168046, 41867034, 42272312), the Opening Fund of State Key Laboratory of Geohazard Prevention and Geoenvironment Protection (Grant No. SKLGP2022K002), the Natural Science Foundation of Jiangsu Province (Grant No. BK20210479) and the Systematic Project of Guangxi Key Laboratory of Disaster Prevention and Engineering Safety (Grant No. 2020ZDK010). The authors appreciate all the financial supports greatly.

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